Aggression between dogs in the same household
Most multi-dog families live happily together throughout their lives. But when it goes wrong, the results are upsetting and miserable for all concerned. Interdog aggression is usually between the same sex and most often between two male dogs. Although less likely between females, when it does occur it is usually much more difficult to stop. This is partially attributable to females having fewer rituals and posturing than male dogs. When female dogs begin to fight, they just go for it!
Interdog aggression usually manifests itself in one of two ways. The most common situation is two dogs or bitches, one older and one younger, which have a good relationship until the younger begins to reach social maturity. This is not to be confused with sexual maturity. Social maturity may occur much later than sexual maturity, not unlike human teenagers! The younger one may start pushing at the status of the older, or the older dog may perceive subtle signals from the younger, and the stability of the relationship will begin to deteriorate.
Many times the younger dog does not actively seek to challenge the more mature dog. The older dog is simply triggered by the normal changes which begin to occur with the maturity of the younger dog.
Another scenario is between two dogs or bitches of similar age and maturity who begin to reach social maturity at the same time and begin to dispute the hierarchical position between the two of them.
In either case, the challenges between the two will usually be over resources such as food, toys, thresholds and, most particularly, the attention of the owners.
This is where it is important for the owner to realise that a dog pack (of which the owners are a part) is not a democracy. Trying to treat the dogs the same will not help and may even exacerbate the problem. Trying to settle the matter according to which dog is your favourite will definitely not help unless the favourite is the more dominant of the two dogs. Unfortunately, the subordinate is very often the big eyed, waggy tailed one which is generally more loving and affectionate to family members.
The dominant dog/bitch is usually more competitive and, even though it may not seek your attention as much as the subordinate, it will object to the other dog gaining access to your attention i.e. the higher ranking dog will often appear more jealous of your attention. Once you have assessed which dog has the edge, your job is to be supportive of the higher ranking dog in its bid for status. If you attempt to regulate the hierarchy artificially between the dogs i.e. support the underdog, you will only make that dogs life miserable.
The dominant dog will continue to vie for rank and the aggression will continue. It is not possible for you to always be there to defend the subordinates position and the top dog will continue to pick on the subordinate over the issues of resources.
So, what can you do? It will help in general if the owners become more aloof to both dogs until the hierarchy is settled between the two dogs. Do not allow demands to be made on you by either dog.
If you can assess which dog is gaining the upper hand, your job is to be supportive of that dog. That dog is to be fed first, petted and greeted first, leash put on first, and allowed through thresholds before the subordinate.
Take control of any resources which trigger aggression. All toys are to be put away, feeding should take place separately, and separate sleeping areas should be established. Bedrooms and entrances to special rooms are by invitation only. When allocating separate sleeping areas, make sure the top dog gets the best place i.e. the sleeping area closest to your own.
Take particular control over threshold areas, which are often the trigger for aggression. Make the point that thresholds which are of particular significance to the dogs (probably doors to the outside) are under your control. Both dogs must sit and wait for an invitation to go in or out.
Remember, that even though you are going to respect the dominant dogs position over the subordinate dog, it does not mean that either dog has a status over yours! You have a right to say what is allowed and not allowed in your house. Trigger signals such as growling and raising of the hackles should be met with a sharp Leave it and separation of the two dogs. Make sure neither dog has your company or attention until everyone calms down. You are in charge here!
Some words of caution. It is never a good idea to involve yourself in a dog fight. Even a dog of the best character may bite indiscriminately when engaged in a fight. If you know your dogs have an aggression problem with each other, it would be best to keep them on a halter type collar and a 6 ft. line while they are in the house.This would allow you to separate the dogs without grabbing at collars. Many times the collar and line has an inhibiting effect on the dogs which, again, is what you need.
The real point that needs to be made here is that the human members of the pack must be the highest ranking. The dogs status cannot be artificially manipulated and it is your job to keep the status quo between them. I hope this information gives you some helpful insight on the pack system and your place in that system. Humankind has been living with dogs for over 6,000 years and it is only fair that we begin to understand life from their point of view.